Currently, on a downlink of a high speed wireless communication system, such as a code division multiple access (CDMA, Code Division Multiple Access) system, each user equipment (UE, User Equipment) generally only knows about some channel information of its own, and a blind interference suppression algorithm is implemented on other UEs. Because the CDMA system and the like are interference limited systems, to employ a higher level interfering user suppression algorithm to improve the system capacity, more related information about the interfering user needs to be acquired, for example, the number of code channels occupied by each UE, and whether a new user accesses the system can be determined by detecting the number of the active code channels.
The existing code channel detecting technology is to determine whether a code channel is active by using a noise threshold, and when the noises are not accurately estimated, it is difficult to achieve a desirable code channel correct detection rate and a desirable false alarm rate in the prior art. Besides, this simple noise threshold determination cannot guarantee that the desirable code channel correct detection rate and false alarm rate are achieved in every interference scenario, especially in a scenario with weak interference.